Narrative of the surveying voyages of his majesty's ships Adventure and Beagle (vol.3)

350 CHONOS ARCHIPELAGO. Jan. 1835. cranberry, but with a sweet beny ; another {Empetntm ru- brum) hke our heath, and a third {Juncus grandiflorus) a rush ; are nearly the only ones that grow on the swampy sur- face. These plants, though possessing a very close general resemblance to the English kinds, are botanically dif- ferent. In the more level parts of the country, the surface of the peat is broken up into little pools of water, which stand at different heights, and appear as if artificially exca- vated. Small streams of water, flowing under ground, com- plete the disorganization of the vegetable matter, and con- solidate the whole. The climate of the southern part of America appears par- ticularly favourable to the production of peat. In the Falk- land Islands, almost every kind of plant, even the coarse grass which covers the whole surface of the island, becomes converted into this substance. I was at first at a loss to imagine how so much peat had been formed ; but the conver- sion of the grass at once explains it. I observed that even some bones of cattle, strewed on the surface, were nearly covered up by the decaying matter at the foot of the blades of withered grass. Scarcely any situation checks its growth; it overhangs the banks of running streams, and encroaches on the piles of loose angular fragments of quartz rock. Some of the beds are of considerable thickness, even as much as twelve feet : the peat in the lower part is earthy, and completely altered, and when dry, becomes so solid that it ignites with difficulty. No doubt, although every plant lends its aid in the process, yet the Astelia is the most efiicient. It is rather a singidar circumstance, as being so very different from what occurs in Europe, that no kind of moss forms by its decay any portion of the peat in South America. With respect to the northern limit at which the climate allows of that pecuhar kind of slow decomposition which is necessary for the production of peat, 1 beheve that in Chiloe (lat. 41° to 42°), although there is much swampy ground, no well-characterized substance of this nature